A method of making a body comprising polycrystalline diamond on a cermet substrate

A method of making a body 60 by subjecting a substrate 30 formed from carbide grains cemented together by a cement material to a first pressure treatment, removing at least some of the cement material from at least a region 34 of the substrate 30 adjacent a boundary 32 defined by the substrate 30 and subjecting the substrate 30 to a second pressure treatment in contact with or bonded at the boundary 32 to a mass of diamond grains 10 or to a polycrystalline diamond compact. The first pressure treatment is performed at a pressure of at least 1 GPa and at a temperature of at least 1000 °C and can be used to join the diamond to the substrate 30. Alternatively the PCD compact can be joined to the substrate 30 during the second pressure treatment, which can be performed at a pressure of at least 5.5 GPa and at a temperature of at least 1200 °C. Used for making earth boring bit cutter inserts.